Treatment of a number of medical disabilities, as for example diabetes, requires continuous application of medication to replace a lost body function. This is often accomplished by a continuous injection by means of a syringe of a medication directly into the blood stream of a patient over a predetermined period of time which often may extend from a few hours to a number of days. In order that the patient not be immoblized, it is desirous that the syringe be of a portable type such that it may be strapped to the patient. This requires that the syringe be small, and from an economic viewpoint, be easily assembled of conveniently manufactured parts.
It is a further requirement in such devices that the dosage of medication be accurately metered to assure that the correct amount of medication is administered over a set predetermined amount of time. Electric motor driven devices have been proposed but such devices are subject to problems of variations in charges of batteries necessary to drive the devices. Spring motor clockwork devices have been proposed but these usually result in relatively large devices which tend to impede mobility of a patient.
Further it is desirable that such devices be capable of having their rate of metering easily changed to accommodate varying rates of application of dosages.
It is therefore an object of the invention to provide for a viscous fluid timed infusion device that is small so as to be easily strapped to a patient in order to keep any immobilization of the patient to a minimum.
It is a further object of the invention to provide for a syringe which is easy to manufacture and assemble and which at the same time provides a highly accurate device for metering application of medication over a predetermined period of time.
It is a still further object to provide for a timed infusion device by which the rate of application of dosage may be easily varied to accommodate various treatments.